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30-seconds-of-code/snippets/get.md
2022-03-22 12:32:56 +02:00

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---
title: Get nested value
tags: dictionary,list
expertise: intermediate
author: maciv
firstSeen: 2020-10-28T12:21:39+02:00
lastUpdated: 2020-10-28T12:21:39+02:00
---
Retrieves the value of the nested key indicated by the given selector list from a dictionary or list.
- Use `functools.reduce()` to iterate over the `selectors` list.
- Apply `operator.getitem()` for each key in `selectors`, retrieving the value to be used as the iteratee for the next iteration.
```py
from functools import reduce
from operator import getitem
def get(d, selectors):
return reduce(getitem, selectors, d)
```
```py
users = {
'freddy': {
'name': {
'first': 'fred',
'last': 'smith'
},
'postIds': [1, 2, 3]
}
}
get(users, ['freddy', 'name', 'last']) # 'smith'
get(users, ['freddy', 'postIds', 1]) # 2
```